Significance of Research: Exo Dynamics seeks to develop a novel active spinal orthosis that will enhance the outcomes of bracing treatment for the most common osteoporotic spinal fractures. The goal is to create a device that will enhance outcomes through monitored use, and provide consistent, continuous support through a complete range of motion (ROM). This device may reduce pain, enhance mobility, lead to a higher quality of life, and reduce the rate of subsequent fractures for patients exiting bracing treatment. Description of the Problem: Patients may exit current bracing treatment with suboptimal mobility and reduced strength in their lower backs due to orthosis-imposed immobilization. Currently, patients are instructed to undergo a ?weaning? process near the end of treatment to counter these effects, but a reliance on patient discipline and crude methods often yields mixed results. Description of Technology and Long Term Goal: Unlike existing passive braces, the proposed brace (or orthosis) will incorporate a closed-loop electromechanical control and actuation system to monitor whether a patient is using the brace, and provide time-dependent adjustment of ROM and perceived stiffness, allowing automated bracing and weaning for spinal Compression Burst Fracture (CBF) patients. The goal is to bring to market this novel medical device with the potential to automate and customize bracing treatment for this large (and growing) patient population, as well as improving ROM, strength, pain levels, and subsequent fractures. Phase I Hypothesis and Specific Aims: An active back brace, a thoracolumbosacral spinal orthosis (TLSO), can be constructed that is capable of supporting 1.5 times the mass of the upper body of a person throughout a specified ROM, and can be worn for two weeks during a simulated bracing and weaning protocol with no visible signs of skin breakdown. The proposed work is organized into three specific aims: the first tests the load-bearing and maneuverability of the mechanical portions of the device, the second tests the active-response support behavior of the electronic control system, and the third is a trial with a small pool of healthy human subjects wearing the device throughout a ?compressed? simulated treatment protocol lasting two weeks. Plans for Phase II: The design of the prototype orthosis will be finalized, incorporating Phase I results. A randomized control study of up to 90 patients in 3 groups (control, standard bracing followed by prototype weaning, prototype bracing and weaning) will then be conducted to study the efficacy of the proposed orthosis. Commercial Application: Up to 750,000 CBFs occur annually in the United States, resulting in up to $18 billion in treatment costs. Nearly 20% of all CBF patients will experience one or more additional fractures within one year of treatment. The spinal orthosis market is projected to be $264.7 million (of which $82.7 million is for custom-fabricated devices) in 2016. Exo Dynamics will assemble and distribute the devices through orthotics & prosthetics centers, with acquisition by an established leader as a potential exit.